As the number of web users who access web services increases, so does the number of such users who do so anonymously. Visitor stitching aims to identify which user logs belong to the same user, even where the logs represent anonymous user sessions. This identification is central to a wide variety of applications on the web that aim to provide personalized services and experiences to users. Unfortunately, visitor stitching can be complicated in that user logs, such as web or cookie logs, corresponding to a single user often span many devices and applications, including a mix of logged-in and anonymous sessions.
Approaches to visitor stitching have compared search behavior, purchase history, and topical and content information between logs to determine whether the logs belong to the same user. This information is unlikely to be universal across separate domains, meaning some logs could lack this information, or it could be expressed inconsistently amongst the logs. Geolocation information tends to be more consistent and available amongst domains. Approaches that employ geolocation information for visitor stitching simply attempt to match IP-addresses across user logs. Thus, the geolocation information is only useful in this limited context.